Requesting documentation on the <OpenApiReference /> element

[EDIT by guardrex to add the metadata]

I see a reference to `` in this document https://docs.microsoft.com/en-us/aspnet/core/web-api/microsoft.dotnet-openapi?view=aspnetcore-3.0#add but there's no real specifics as to what the settings are for it. I see ClassName OutputPath SourceUri and Options and least as sub elements but I'm not seeing any description for them, like what the full set of options are.

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#### Document Details

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* ID: 653e14ef-227e-a165-0360-2f59259e16c6
* Version Independent ID: e4685d05-e874-76a3-9780-66b864eca6c1
* Content: [Develop ASP.NET Core apps using OpenAPI](https://docs.microsoft.com/en-us/aspnet/core/web-api/microsoft.dotnet-openapi?view=aspnetcore-3.0)
* Content Source: [aspnetcore/web-api/Microsoft.dotnet-openapi.md](https://github.com/aspnet/AspNetCore.Docs/blob/master/aspnetcore/web-api/Microsoft.dotnet-openapi.md)
* Product: **aspnet-core**
* Technology: **aspnetcore-webapi**
* GitHub Login: @ryanbrandenburg
* Microsoft Alias: **rybrande**